Build your own ioGun!

I apologize for what will effectively be a brain dump post, but a new friend of mine from the hackaday forums is getting started on his own accelerometer controlled system and I wanted to see if I could save him some time and frustration.

I think standing on the shoulders of Giants is a fantastic aspect of human nature, now if only someone could show me to some friendly Cyclopi (is that really the right pluralization?), and frankly I could not exist, let along thrive in the technological world if it were for the good graces of a great many people.

Perhaps I will write a _very long_ blog thank-you to them (if I can remember them all). So consider this my little chance at saving some of you a few hours of your precious time (and brain strain). Because of the very nature of hacking (i.e. everything’s just a little different and throw together) this can’t quite be the same quality as an instructable but it should get some of you started!

I’ve put up my code here so that’s quite obviously the place to start. You’ll find a python script and an HTML page. The script connects to the MoteDaemon port I referenced earlier and will write these data points out to a JSON file which can be served via your webserver, and is then picked up by the HTML page.

If you look through the code you’ll see there’s clearly some tuning that can be done. As people on many forums pointed out there’s a “lag” which is really just because of my polling rates (and less to do with the network traffic).

Two important things here, first you’ll see that I created a separate thread for the monitoring and one for the output, that’s because the wiimote data is fast and furious and you don’t want to block and miss any!

Second, I know writing to an JSON file isn’t ideal so the output part actually buffers 10 events and writes those, luckily jQuery is smart enough to only pull the file if it’s changed so it’s not as bad as it sounds.

Once you’ve got the accelerometer data into python (and then into JSON) it’s ‘just’ a matter of writing the webpage you want! jQuery makes some stuff really easy so I suggest giving it a look if you haven’t yet!

Of course what makes it really easy for me was the ioBridge module. I just plugged in a servo there and defined a widget on their page and ‘viola I had a webservice I could send commands to!

I hope that helps give some of you (or at least one of you) a boost, and if I can help out at all please let me know!

About jay

I'm trying to build something interactive where I can learn from others and hopefully share useful knowledge too.
thecapacity@gmail.com